The Closed-Oven Method
- Gather the ingredients.
- The night before cooking the prime rib, unwrap the roast and let it sit uncovered in the refrigerator. This will dry out the surface, which makes it easier to get a nice brown color on the roast.
- Three hours before you want to begin cooking, take the roast out of the fridge and place it on a sheet pan ribs down at room temperature.
- Half an hour before you start roasting, pre-heat your oven to 500 F and season the roast generously with
Kosher salt and freshly ground black pepper. I replaced with the rub below.
- Now it’s time to do your calculation. Simply multiply the weight of your roast by five. That’s your total roasting time, in minutes. For instance, if you have a 4-pound roast, 4 × 5 = 20 minutes. An 8-pound roast? 8 × 5 = 40 minutes. Remember that number.
- When you’re ready to cook, set the roast in a roasting pan with a rack, fat-side-up.
If you’re nervous about the cooking time, you can insert a meat thermometer or a digital probe thermometer into the deepest part of the meat, being careful not to hit bone.
- Put the roast in the preheated oven and roast it for exactly however many minutes you calculated above. When the time’s up, turn off the oven and walk away. Do not open the oven door for any reason for the next two hours.
- In two hours, take the prime rib out of the oven, carve, and serve right away. If you did use a thermometer, you’ll see that the internal temperature of the meat has reached 130 F, perfect medium-rare.
- Remove the ribs.
- Cut cross-wise, serve with horseradish sauce.
- For a bone-in prime rib, figure two servings per rib, while a boneless roast will yield two servings per pound.
- When trying to figure out how much time you need to roast your prime rib, use this simple calculation: weight of the prime rib x 5 = total roasting time in minutes. For example, if you have a 3-pound roast, 3 × 5 = 15 minutes. A 6-pound roast? 6 × 5 = 30 minutes.
10 cloves garlic, minced
2 tablespoons olive oil
2 teaspoons salt
2 teaspoons ground black pepper
2 teaspoons dried thyme
Horseradish Cream Sauce
3/4 cup (6 fl. oz./180 ml) heavy cream
1 cup (8 fl. oz./250 ml) sour cream
1/2 cup (3 oz./90 g) freshly grated or prepared horseradish
Juice of 1 lemon
Kosher salt and freshly ground pepper, to taste